1. Field of the Invention
The present invention generally relates to a method of and an apparatus for preventing a structure from collapsing by earthquake shocks and torsional moment during an earthquake. More particularly, it relates to a method of an apparatus for preventing a structure from being wrecked by making them be raised and separated from the surface of the ground (for example, the present invention is actuated at the 7th degree on the seismic scale in case that the structure is designed to withstand lateral seismic stresses of 8th degree) when there is a great earthquake enough to demolish structures such as houses and multi-storied buildings.
2. Description of the Prior Art
Structures including buildings, bridges, towers, fortresses, etc. are built on the ground from the underground, and they are designed and built strongly enough to withstand external shocks or seismic stresses of a given degree as well as their own load or loads of various things that are placed on them.
However, the conventional structures may be easily wrecked by a very strong earthquake whose intensity is higher than their own resistance against the earthquake. The earthquake is a series of suddenly generated elastic waves in the earth caused by movement of the earth""s crust, the structures built perpendicularly on the surface of the ground receive torsional moment when the earthquake shock gets to the surface of the ground. When an earthquake with such a moment exceeding the limit of the earthquake proof architecture, the structures become wrecked.
There are many earthquake zones in the earth, and the areas near these earthquake zones have had a loss of lives and property damage by the collapse of structures due to the occurrence of earthquakes. In order to obviate the above problems, the present inventor developed a method of and an apparatus for preventing collapse of structures due to earthquakes and filed a Korea patent application for this invention (Korean patent application No. 97-22349). According to this application No. 97-22349, a structure is designed to go down to a guard construction, built under the ground, during an earthquake, and cannot provide protection to the structure and lives in the structure against the earthquake.
In the application No. 97-22349, a structure cannot go down to its guard construction until water is supplied to its water chamber when an earthquake is generated. Thus, if the water supply system is damaged by the earthquake, the above invention cannot achieve the object of preventing the collapse of a structure due to an earthquake, and since its weights, provided to the underground guard construction, are directly connected to the structure via balance cables, the earthquake shocks may be delivered to the structure through its balance cables.
Accordingly, the present invention is directed to a method of and an apparatus for preventing the collapse of a structure due to an earthquake that substantially obviate the problems due to limitations and disadvantages of the related art.
It is an object of the present invention to provide a method of and an apparatus for preventing the collapse of a structure due to an earthquake by making the structure be moved up and separated from the surface of the ground not to receive torsional moment when there is a great earthquake of a given intensity.
It is another object of the present invention to provide a method of and an apparatus for preventing the collapse of a structure via earthquake-proof means not to deliver earthquake shocks to the structure through the balance cables connected to weights.
It is still another object of the present invention to provide a method of and an apparatus for obviating the collapse of a structure due to an earthquake and for precluding loss of lives and property damage.
In order to obtain the above-mentioned objects of the present invention, there is disclosed a method of preventing collapse of a structure due to an earthquake by using a construction with a water chamber whose outside contacts a receiving area, provided to the earth""s surface, and balance cables each connected to a plurality of weights and variable weights a little lighter than the total weight of the structure""s own weight, variable weight of things and people within the structure, and the weight of the water in the water chamber. The structure with the water chamber is separated from the receiving area and raised form the earth""s surface by draining off the water in the water chamber during an earthquake, and returns to its original position by increasing the weight of the water chamber once the earthquake completely stops.
According to another aspect of the present invention, an apparatus for preventing collapse due to an earthquake, includes a receiving area provided to the earth""s surface where a structure is to be built; a plurality of balancing chambers equidistantly provided on all sides of the receiving area; a water chamber built under the structure and having an outside closely contacting the receiving area; a balance weight provided to the bottom of the water chamber and serving as a center of gravity; sand provided around the balance weight to distribute vibrations; and an earthquake-proof means installed on the upper part of the water chamber in order to prevent seismic waves from being delivered to the structure through balance cables.